LED module

ABSTRACT

A LED module includes a substrate, a LED chip supported on the substrate, a metal wiring installed on the substrate, the metal wiring including a mounting portion on which the LED chip is mounted, an encapsulating resin configured to cover the LED chip and the metal wiring, and a clad member configured to cover the metal wiring to expose the mounting portion, the encapsulating resin arranged to cover the clad member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of application Ser. No. 14/230,631,filed Mar. 31, 2014, which is a Continuation of application Ser. No.13/397,110, filed Feb. 15, 2012, which is based upon and claims thebenefit of priority from Japan Patent Application Nos. 2012-008741 and2011-30331, filed on Jan. 19, 2012 and Feb. 16, 2011, respectively, theentire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a LED module having a light emittingdiode (hereinafter referred to as a “LED”) arranged therein.

BACKGROUND

One example of a LED module is shown in FIG. 10. The LED module X shownin FIG. 10 includes a substrate 91, metal electrodes 92 and 93 arrangedin the substrate 91, a LED chip 94 electrically connected to the metalelectrodes 92 and 93, a wire 95 and an encapsulating resin 96 coveringthese components. The substrate 91 is made of, e.g., a glass epoxyresin. The metal electrodes 92 and 93 are spaced apart from each otherat the opposite marginal edges of the substrate 91. Each of the metalelectrodes 92 and 93 covers a region extending from the front surface ofthe substrate 91 to the rear surface across the side surface. The LEDchip 94 is mounted on the portion of the metal electrode 92 covering thefront surface of the substrate 91. One end of the wire 95 is fixed tothe portion of the metal electrode 93 covering the front surface of thesubstrate 91. The other end of the wire 95 is connected to the LED chip94. The LED module X, when in use, is embedded to, e.g., a circuit board97 built in an illuminating device. As shown in FIG. 10, the portions ofthe metal electrodes 92 and 93 covering the rear surface of thesubstrate 91 are connected to wiring lines 98 provided in the circuitboard 97. When installing the LED module X on the circuit board 97, aprocess is performed in which the LED module X and the circuit board 97are heated in a reflow furnace with solder materials inserted betweenthe metal electrodes 92 and 93 and the wiring lines 98.

The encapsulating resin 96 is provided to protect the LED chip 94 andthe wire 95 and is formed of an epoxy resin transparent to the lightemitted from the LED chip 94. The encapsulating resin 96 is formed tocover the portions of the metal electrodes 92 and 93 positioned on thefront surface of the substrate 91. Gold-plated layers are often formedon the surfaces of the metal electrodes 92 and 93 in order to increasethe conductivity. However, the epoxy resin and the gold are not easilybonded to each other, possibly posing a problem set forth below. Asstated above, a heating process is performed when installing the LEDmodule X on the circuit board 97. At this time, the encapsulating resin96 is thermally deformed. However, the encapsulating resin 96 and themetal electrodes 92 and 93 may be exfoliated, since the epoxy resin andthe gold-plated layer are not strongly bonded together. If suchsituation occurs, there is a possibility that the LED chips 94 are notturned on.

SUMMARY

The present disclosure provides some embodiments of a highly reliableLED module conceived in view of the afore-mentioned circumstances.

According to one aspect of the present disclosure, there is provided aLED module. The LED module includes a substrate, a LED chip, a metalwiring, an encapsulating resin and a clad member. The LED chip issupported on the substrate. The metal wiring is installed on thesubstrate and has a mounting portion on which the LED chip is mounted.The encapsulating resin covers the LED chip and the metal wiring. Theclad member covers the metal wiring to expose the mounting portion. Withthis configuration, the encapsulating resin is arranged to cover theclad member.

In one embodiment, the clad member has an opening formed to permitinstallation of the LED chip when seen in a thickness direction of thesubstrate.

For example, the mounting portion has a rectangular shape when seen inthe thickness direction of the substrate, and the opening has a circularshape when seen in the thickness direction of the substrate.

In another embodiment, the clad member partially covers the mountingportion.

In another embodiment, the metal wiring includes a wire bonding portionspaced apart from the mounting portion, and a wire configured tointerconnect the LED chip and the wire bonding portion. The clad memberis arranged to cover the metal wiring to expose the wire bondingportion.

In another embodiment, the clad member has a recess dented to approachthe mounting portion in an extension direction of the wire. The recessis positioned to overlap with the wire bonding portion when seen in thethickness direction of the substrate.

In another embodiment, the metal wiring includes a first metal electrodecontaining the mounting portion and a second metal electrode containingthe wire bonding portion. The first metal electrode covers a first edgeof the substrate in a first direction. The second metal electrode coversa second edge of the substrate opposite the first edge. Theencapsulating resin is shorter than the substrate.

In another embodiment, the substrate includes a pair of concave portionslocated at opposite ends of the substrate, the pair of concave portionsincluding depressed toward one another. The metal wiring is arranged tocover the pair of the concave portions, and the encapsulating resin isformed to expose the pair of the concave portions.

In another embodiment, a first end of the clad member and a first end ofthe encapsulating resin are at the same position in the first direction.

In another embodiment, a first end of the clad member extends toward afirst end of the substrate further than a first end of the encapsulatingresin in the first direction.

In another embodiment, a second end of the clad member and a second endof the encapsulating resin are at the same position in the firstdirection.

In another embodiment, a second end of the clad member extends furthertoward a second end of the substrate than a second end of theencapsulating resin in the first direction.

In another embodiment, the encapsulating resin is formed to cover entirewidth of the substrate in a second direction orthogonal to the firstdirection. The opposite ends of the clad member and the opposite ends ofthe substrate are at the same position in the second direction.

In another embodiment of the present disclosure, the substrate is formedlonger than the encapsulating resin in the first direction. A first sidesurface of the encapsulating resin inclines toward a second side surfacein the first direction.

For example, the first side surface of the encapsulating resin includesan inclined surface inclined 6 degrees or more with respect to thethickness direction of the substrate.

In an additional embodiment, the first side surface of the encapsulatingresin has a curved surface.

The second side surface of the encapsulating resin inclines toward thefirst side surface in the first direction.

For example, the second side surface of the encapsulating resin includesan inclined surface inclined 6 degrees or more with respect to thethickness direction of the substrate.

In an additional embodiment, the second side surface of theencapsulating resin includes a curved surface.

In yet another embodiment of the present disclosure, the clad member ismade of a material with which the adhesion strength between the cladmember and the metal wiring and the adhesion strength between the cladmember and the encapsulating resin become greater than the adhesionstrength between the metal wiring and the encapsulating resin.

For example, the metal wiring has a gold-plated layer.

For example, the clad member is made of a resin.

For example, the clad member has a white color.

For example, the clad member has a thickness of 1 μm to 10 μm.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present disclosure will become moreapparent from the following detailed description of some embodimentsmade in conjunction with the accompanying drawings.

FIG. 1 is a plan view showing a LED module according to a firstembodiment of the present disclosure.

FIG. 2 is a section view taken along line II-II in FIG. 1.

FIG. 3 is a plan view of the LED module shown in FIG. 1, with anencapsulating resin omitted for clarity.

FIG. 4 is a plan view showing a LED module according to a secondembodiment of the present disclosure, with an encapsulating resinomitted for clarity.

FIG. 5 is a section view showing a LED module according to a thirdembodiment of the present disclosure.

FIG. 6 is a section view showing a LED module according to a fourthembodiment of the present disclosure.

FIG. 7 is a section view showing a LED module according to a fifthembodiment of the present disclosure.

FIG. 8 is a plan view showing a LED module according to a sixthembodiment of the present disclosure, with an encapsulating resinomitted for clarity.

FIG. 9 is a plan view showing a LED module according to a seventhembodiment of the present disclosure, with an encapsulating resinomitted for clarity.

FIG. 10 is a section view illustrating one example of conventional LEDmodules.

DETAILED DESCRIPTION

Some embodiments of the present disclosure will now be described indetail with reference to the drawings.

FIGS. 1 through 3 show a LED module according to a first embodiment ofthe present disclosure. The LED module A1 shown in FIGS. 1 through 3includes a substrate 1, a metal wiring 2, a LED chip 3, an encapsulatingresin 4, a wire 5 and a clad member 6. In FIG. 3, the encapsulatingresin 4 is omitted to illustrate the interior of the LED module A1. Thex, y and z directions indicated in FIGS. 1 through 3 are orthogonal toone another. The z direction is the thickness direction of the substrate1. In the following description, the upper surface of the substrate 1 inthe z direction in FIG. 2 will be referred to as a front surface, thelower surface as rear surface and the opposite end surfaces in the xdirection as side surfaces.

The substrate 1 is made of, e.g., a glass epoxy resin. When seen in thez direction as in FIG. 3, the substrate 1 has an elongated rectangularshape extending in the x direction. A pair of concave portions 1 adepressed in the x direction is formed in opposite end portions of thesubstrate 1 in the x-direction. The substrate 1 is manufactured, forexample, by cutting a substrate material. In the manufacturing process,a plurality of through-holes is formed in the substrate material. Theconcave portions 1 a are formed by cutting the through-holes.

The metal wiring 2 includes a metal electrode 21 and a metal electrode22. The metal electrode 21 and the metal electrode 22 are spaced apartfrom each other in the x-direction and arranged at opposite edges of thesubstrate 1. Each of the metal electrodes 21 and 22 covers a regionextending from the front surface of the substrate 1 to the rear surfaceacross the side surface. In the present embodiment, the metal electrodes21 and 22 cover only the concave portions 1 a of the side surfaces ofthe substrate 1. The regions of the metal electrode 21 and the metalelectrode 22 positioned on the front surface of the substrate 1 are usedin mounting the LED module A1 to a desired circuit board as describedearlier.

As shown in FIG. 3, the metal electrode 21 includes a region coveringthe left end portion of the substrate 1 over the full width in the ydirection. The metal electrode 21 further includes a narrow band portion211 protruding from the region toward the x-direction, which is theright direction in FIG. 3. In addition, a mounting portion 212 connectedto the right end of the narrow band portion 211 in the x-direction isalso included in the metal electrode 21. In the example shown in FIG. 3,the mounting portion 212 has a square shape when seen in the zdirection. The length of one side of the mounting portion 212 is largerthan the length of one side of the LED chip 3 but is smaller than they-direction width of the substrate 1. The narrow band portion 211 isformed such that the y-direction width thereof becomes smaller than thelength of one side of the mounting portion 212.

As illustrated in FIG. 3, the metal electrode 22 includes a regioncovering the right end portion of the substrate 1 over the full width inthe y direction and a narrow band portion 221 protruding from the regiontoward the x-direction, which is the left side in FIG. 3. In the exampleillustrated in FIG. 3, the y-direction width of the narrow band portion221 is smaller than the length of one side of the mounting portion 212.The right end in FIG. 3 of the wire 5 is connected to the narrow bandportion 221. The section of the narrow band portion 221 not covered withthe clad member 6 corresponds to a wire bonding section referred to inthe present disclosure.

While omitted in the example shown in FIG. 2, the metal wiring 2 isformed of a plurality of metal layers laminated one above another. Amongthe metal layers, the outermost metal layer is formed of gold. The metalwiring 2 can be formed by subjecting the afore-mentioned substratematerial to a plating treatment and etching away unnecessary portions.At this time, a structure in which the metal wiring 2 covers the concaveportions 1 a can be easily realized by performing the plating treatmentto cover the inner circumferential surfaces of the through-holes formedin the substrate material.

The LED chip 3 is, e.g., a pn-type semiconductor device, and isconfigured to emit visible light or infrared light. The LED chip 3 hasan n-side electrode formed on the lower surface thereof in FIG. 2. Then-side electrode is electrically connected to the mounting portion 212through a silver paste which is not shown. The LED chip 3 has a p-sideelectrode formed on the upper surface thereof in FIG. 2. The p-sideelectrode is electrically connected to the narrow band portion 221through the wire 5.

The encapsulating resin 4 is provided to protect the LED chip 3 and thewire 5, and is formed of, e.g., an epoxy resin transparent to the lightemitted from the LED chip 3. The x-direction length of the encapsulatingresin 4 is smaller than the x-direction length of the substrate 1. They-direction length of the encapsulating resin 4 is equal to they-direction length of the substrate 1. As shown in FIG. 1, theencapsulating resin 4 has an x-direction left end 4 a positioned at theright side of the left concave portion 1 a of the substrate 1 and anx-direction right end 4 b positioned at the left side of the rightconcave portion 1 a of the substrate 1. As shown in FIG. 2, thex-direction left side surface 41 of the encapsulating resin 4 is aninclined surface, which is positioned to the x-direction right side asit extends toward the upper side in the z direction. The side surface 41is inclined 6 degrees or more with respect to the z direction. Thex-direction right side surface 42 of the encapsulating resin 4 is aninclined surface, which is positioned at the x-direction left side as itextends toward the upper side in the z direction. The side surface 42 isinclined 6 degrees or more with respect to the z direction. Theencapsulating resin 4 can be formed by a transfer molding method. Thetransfer molding method includes a step of installing theafore-mentioned substrate material in a mold and filling a molten resininto the mold and a step of pulling the mold and the substrate materialapart after the resin is cured.

The wire 5 is made of gold and is formed through the use of, e.g., acommercially available wire bonding capillary.

As shown in FIG. 2, the clad member 6 covers the metal wiring 2 and iscovered with the encapsulating resin 4. The clad member 6 is made of amaterial with which the adhesion strength between the clad member 6 andthe metal wiring 2 and the adhesion strength between the clad member 6and the encapsulating resin 4 become greater than the adhesion strengthbetween the metal wiring 2 and the encapsulating resin 4. For example,the clad member 6 may be a resin film having a z-direction thickness of1 μm to 10 μm. As the resin film, it is possible to use, e.g., a resistemployed in an etching process. It may also be possible to use a solderresist employed in a soldering process. If a white resist is used as theclad member 6, it becomes easy for the clad member 6 to reflect thelight emitted from the LED chip 3. For that reason, the use of the whiteresist as the clad member 6 may provide an effect of increasing thequantity of light emitted in the z direction from the LED module A1.

In the example shown in FIG. 3, the clad member 6 is formed at least ina region other than a region where the LED chip 3 is die-bonded and aregion where the wire 5 is bonded. The clad member 6 includes a firstclad member 61 and a second clad member 62 spaced apart from each otherin the x direction. As shown in FIG. 3, the first clad member 61 isformed into an elongated rectangular shape extending in the y directionwhen seen in the z direction. The y-direction length of the first cladmember 61 is smaller than the y-direction length of the substrate 1. Thex-direction right end portion of the first clad member 61 partiallycovers the narrow band portion 211. As shown in FIG. 2, the x-directionleft end 61 a of the first clad member 61 lies in the same position asthe x-direction left end 4 a of the encapsulating resin 4 in the xdirection.

As shown in FIG. 3, the second clad member 62 is formed into anelongated rectangular shape extending in the y direction when seen inthe z direction. The y-direction length of the second clad member 62 issmaller than the y-direction length of the substrate 1. The x-directionleft end portion of the second clad member 62 partially covers thenarrow band portion 221. As shown in FIG. 2, the x-direction right end62 a of the second clad member 62 lies in the same position as thex-direction right end 4 b of the encapsulating resin 4 in the xdirection. In addition, the first clad member 61 is formed to cover notonly the upper surface in FIG. 2 of the metal electrode 21 of the metalwiring 2 but also the front surface of the substrate 1. The second cladmember 62 is formed to cover not only the upper surface in FIG. 2 of themetal electrode 22 of the metal wiring 2 but also the front surface ofthe substrate 1.

Next, description will be made on the operation of the LED module A1.

In the LED module A1 set forth above, the clad member 6 is providedbetween the metal wiring 2 and the encapsulating resin 4. As stated inthe description of the example, if a gold layer is formed on the surfaceof the metal wiring 2, it causes a problem in that the metal wiring 2and the encapsulating resin 4 are not easily bonded to each other, whileit provides superior conductivity. In the LED module A1, an attempt ismade to solve the problem by inserting the clad member 6 between themetal wiring 2 and the encapsulating resin 4. Thus the LED module A1 hasa configuration that is easy to enhance the reliability thereof.

In the LED module A1, the side surfaces 41 and 42 of the encapsulatingresin 4 are formed of inclined surfaces. This helps to prevent theencapsulating resin 4 from being caught in a mold when pulling the moldapart from the substrate material after a resin is cured in a transfermolding method. If the encapsulating resin 4 is caught in the mold, aforce is applied for a long period of time in a direction in which theencapsulating resin 4 and the substrate 1 are pulled apart from eachother. This increases the risk of causing exfoliation of theencapsulating resin 4 from the metal wiring 2. The LED module A1 iscapable of preventing such problem and, therefore, has a configurationthat assists in enhancing the reliability thereof.

In the example shown in FIG. 3, the y-direction length of the cladmember 6 is smaller than the y-direction length of the substrate 1.Alternatively, the y-direction length of the clad member 6 may be equalto the y-direction length of the substrate 1.

In the embodiment described above, the clad member 6 does not protrudeoutward from the encapsulating resin 4. Alternatively, the clad member 6may protrude outward from the encapsulating resin 4.

FIGS. 4 through 9 show other embodiments of the present disclosure. Inthese figures, the components identical with or similar to those of theforegoing embodiment will be designated by the same reference symbols asused in the foregoing embodiment. Description of these components willbe omitted, if appropriate.

FIG. 4 shows a LED module A2 according to a second embodiment of thepresent disclosure. The LED module A2 shown in FIG. 4 differs in shapefrom the clad member 6 from the LED module A1. Other configurations ofthe LED module A2 remain the same as those of the LED module A1. FIG. 4is a plan view of the LED module A2 with the encapsulating resin 4thereof omitted for clarity.

As shown in FIG. 4, the clad member 6 of the present embodiment isformed to cover almost all portions of the substrate 1 except theopposite end portions thereof when seen in the z direction. The cladmember 6 includes an opening 63 through which the mounting portion 212is partially exposed and a recess 64 through which the narrow bandportion 221 is partially exposed.

In a region other than the regions where the opening 63 and the recess64 are formed, the clad member 6 of the LED module A2 covers thesubstrate 1 over the full length in the y-direction. In the x-directionopposite ends 65 and 66 of the clad member 6 may overlap with thex-direction opposite ends (see 4 a and 4 b in FIG. 1) of theencapsulating resin 4 which is not shown. The clad member 6 may protrudeoutward from the encapsulating resin 4.

In the example shown in FIG. 4, the opening 63 has a circular shape whenseen in the z direction. The four corners of the mounting portion 212are covered with the clad member 6. The size of the opening 63 may beset to have an area great enough to permit installation of the LED chip3 and can be changed, if appropriate.

In the example shown in FIG. 4, the recess 64 is formed so that it canbe depressed from the x-direction right end 66 of the clad member 6toward the x-direction left side. The recess 64 may expose the narrowband portion 221 over an area only required in bonding the wire 5 to thenarrow band portion 221. The shape of the recess 64 can be changed, ifappropriate.

The clad member 6 may be greater in the reflectance of the light emittedfrom the LED chip 3 than the substrate 1. As shown in FIG. 4, the frontsurface of the substrate 1 is covered with the clad member 6. The cladmember 6 employed in the present embodiment has a relatively highreflectance. Therefore, as compared with when the front surface of thesubstrate 1 is not covered with the clad member 6, it is possible toenhance the light extraction efficiency. On the contrary, if thereflectance of the clad member 6 is smaller than that of the substrate1, the area of the front surface of the substrate 1 covered with theclad member 6 may be made smaller as is the case in FIG. 1, or the cladmember 6 may be formed to cover only the upper surface of the metalwiring 2 as is illustrated in FIG. 9.

FIG. 5 shows a LED module A3 according to a third embodiment of thepresent disclosure. In the LED module A3 shown in FIG. 5, the edges ofthe encapsulating resin 4 are formed into a round shape. Otherconfigurations of the LED module A3 remain the same as those of the LEDmodule A1.

In the present embodiment, curved surfaces 43 and 44 are providedbetween the side surfaces 41 and 42 and the z-direction upper surface ofthe encapsulating resin 4 in FIG. 5. By providing the curved surfaces 43and 44, it is possible to provide an effect of further reducing aresistance when the encapsulating resin 4 is pulled out from the mold.

FIG. 6 shows a LED module A4 according to a fourth embodiment of thepresent disclosure. In the LED module A4 shown in FIG. 6, the cladmember 6 is formed to protrude from the encapsulating resin 4. Otherconfigurations of the LED module A4 remain the same as those of the LEDmodule A3.

As shown in FIG. 6, the left end 61 a of the first clad member 61 ispositioned at the left side of the left end 4 a of the encapsulatingresin 4 in the x direction. In the example shown in FIG. 6, the left end61 a of the first clad member 61 reaches the left end of the metalwiring 2. Alternatively, the left end 61 a of the first clad member 61may be positioned between the left end 4 a of the encapsulating resin 4and the left end of the metal wiring 2.

The right end 62 a of the second clad member 62 is positioned at theright side of the right end 4 b in FIG. 6 of the encapsulating resin 4in the x direction. In the example shown in FIG. 6, the right end 62 aof the second clad member 62 reaches the right end of the metal wiring2. Alternatively, the right end 62 a of the second clad member 62 may bepositioned between the right end 4 b of the encapsulating resin 4 andthe right end of the metal wiring 2.

FIG. 7 shows a LED module A5 according to a fifth embodiment of thepresent disclosure. In the LED module A5 shown in FIG. 7, the cladmember 6 is formed to be embedded into the encapsulating resin 4. Otherconfigurations of the LED module A5 remain the same as those of the LEDmodule A3.

As shown in FIG. 7, the left end 61 a of the first clad member 61 ispositioned at the right side of the left end 4 a of the encapsulatingresin 4 in the x direction. The right end 62 a of the second clad member62 is positioned at the left side of the right end 4 b of theencapsulating resin 4 in the x direction.

FIG. 8 shows a LED module A6 according to a sixth embodiment of thepresent disclosure. In the LED module A6 shown in FIG. 8, an opening 67having a circular shape when seen in the z direction is formed in placeof the recess 64. Other configurations of the LED module A6 remain thesame as those of the LED module A2.

With this configuration, the clad member 6 may cover the metal wiring 2over a broader area, thereby further restraining exfoliation of theencapsulating resin 4.

FIG. 9 shows a LED module A7 according to a seventh embodiment of thepresent disclosure. In the LED module A7 shown in FIG. 9, the cladmember 6 is formed to cover only the upper surface of the metal wiring2. Other configurations of the LED module A7 remain the same as those ofthe LED module A1. As stated above, this configuration is effective whenthe clad member 6 is smaller in reflectance than the substrate 1.

The LED modules according to the present disclosure are not limited tothe embodiments described above. The specific configurations of therespective parts of the LED modules according to the present disclosuremay be modified to many different designs.

For example, while an example in which die-bonding and wire-bonding areperformed has been described in the foregoing embodiments, the presentdisclosure may be applied to an embodiment in which wire-bondingportions are provided in left and right electrodes and in which a LEDchip and two wire-bonding portions are connected to each other by wirebonding. Moreover, the present disclosure may be applied to anembodiment in which a LED chip is flip-chip connected to left and rightelectrodes. In any event, the clad member is formed in a region otherthan the connection portions of the LED chip and the metal wiring.

According to the above embodiments of the present disclosure, it ispossible to ameliorate the problem of the metal wiring and theencapsulating resin being hard to be bonded to each other, because theclad member is inserted between the metal wiring and the encapsulatingresin. According to some embodiments of the present disclosure, whenmanufacturing the LED module, it is easy to pull out the encapsulatingresin from the mold after the encapsulating resin is formed through theuse of the mold. This helps to reduce the force exerted between theencapsulating resin and the substrate and prevent exfoliation of theencapsulating resin from the metal wiring. Accordingly, the LED moduleprovided by the present disclosure becomes highly reliable.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosures. Indeed, the novel LED modules described hereinmay be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the embodimentsdescribed herein may be made without departing from the spirit of thedisclosures. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the disclosure.

What is claimed is:
 1. A LED module, comprising: a substrate; a LED chip supported on the substrate; a metal wiring installed on the substrate, the metal wiring including a mounting portion on which the LED chip is mounted; an encapsulating resin configured to cover the LED chip and the metal wiring; and a clad member configured to cover an upper surface of the metal wiring, wherein the encapsulating resin is arranged to cover the clad member, and wherein an area of the metal wiring not covered by the clad member is smaller than an area of the clad member in contact with the encapsulating resin.
 2. The LED module of claim 1, wherein the clad member has an opening formed to permit installation of the LED chip when seen in a thickness direction of the substrate.
 3. The LED module of claim 2, wherein the mounting portion has a rectangular shape when seen in the thickness direction of the substrate, and the opening has a circular shape when seen in the thickness direction of the substrate.
 4. The LED module of claim 3, wherein the clad member partially covers the mounting portion.
 5. The LED module of claim 1, wherein the metal wiring includes a wire bonding portion spaced apart from the mounting portion, and a wire configured to interconnect the LED chip and the wire bonding portion, the clad member arranged to cover the metal wiring to expose the wire bonding portion.
 6. The LED module of claim 5, wherein the clad member includes a recess dented to approach the mounting portion in an extension direction of the wire, the recess positioned to overlap with the wire bonding portion when seen in the thickness direction of the substrate.
 7. The LED module of claim 5, wherein the metal wiring includes a first metal electrode containing the mounting portion and a second metal electrode containing the wire bonding portion, the first metal electrode formed to cover a first edge of the substrate in a first direction, the second metal electrode formed to cover a second edge of the substrate opposite the first edge, the encapsulating resin being shorter than the substrate.
 8. The LED module of claim 7, wherein the substrate includes a pair of concave portions formed at opposite ends of the substrate, the pair of concave portions depressed toward one another, the metal wiring arranged to cover the pair of the concave portions, the encapsulating resin formed to expose the pair of the concave portions.
 9. The LED module of claim 7, wherein a first end of the clad member and a first end of the encapsulating resin are at the same position in the first direction.
 10. The LED module of claim 7, wherein a first end of the clad member extends toward a first end of the substrate further than a first end of the encapsulating resin in the first direction.
 11. The LED module of claim 9, wherein a second end of the clad member and a second end of the encapsulating resin are at the same position in the first direction.
 12. The LED module of claim 9, wherein a second end of the clad member extends further toward a second end of the substrate than a second end of the encapsulating resin in the first direction.
 13. The LED module of claim 7, wherein the encapsulating resin is formed to cover entire width of the substrate in a second direction orthogonal to the first direction, the opposite ends of the clad member and opposite ends of the substrate being at the same positions in the second direction.
 14. The LED module of claim 1, wherein the substrate is formed longer than the encapsulating resin in a first direction, a first side surface of the encapsulating resin inclining toward a second side surface in the first direction.
 15. The LED module of claim 14, wherein the first side surface of the encapsulating resin includes an inclined surface inclined 6 degrees or more with respect to the thickness direction of the substrate.
 16. The LED module of claim 4, wherein the first side surface of the encapsulating resin has a curved surface.
 17. The LED module of claim 14, wherein the second side surface of the encapsulating resin inclines toward the first side surface in the first direction.
 18. The LED module of any one of claim 17, wherein the second side surface of the encapsulating resin includes an inclined surface inclined 6 degrees or more with respect to the thickness direction of the substrate.
 19. The LED module of claim 18, wherein the second side surface of the encapsulating resin is a curved surface.
 20. The LED module of claim 1, wherein the clad member is made of a material with which the adhesion strength between the clad member and the metal wiring and the adhesion strength between the clad member and the encapsulating resin become greater than the adhesion strength between the metal wiring and the encapsulating resin.
 21. The LED module of claim 1, wherein the metal wiring includes a gold-plated layer.
 22. The LED module of claim 21, wherein the clad member is made of a resin.
 23. The LED module of claim 22, wherein the clad member has a white color.
 24. The LED module of claim 1, wherein the clad member has a thickness of 1 μm to 10 μm. 